The Witches of Merribay (The Seaforth Chronicles) (Volume 1)

Living in Maine with her grandmother and eccentric aunts is not how sixteen-year-old Ivy Seaforth expected to spend her summer—but working for a peculiar wealthy man and running errands for a powerful witch who lives in a tree-house wasn't in her plans, either. And her sister, Zinnia...something was different. Zinnia was making mysterious visits to the forest, and that was certainly forbidden. Ivy longed for the days when she and her sister were best friends. Those days now seemed so long ago. Ivy soon discovers that, along with the witch, the forest is inhabited by a wondrous race of otherworldly and unearthly beautiful beings - the Fae, and a young man of an even fairer race. When her father disappears, Ivy, must help the old witch break an evil curse that is preventing her from finding him. As she discovers her own mysterious past for the first time, she must learn to accept that things are not always as they seem and that magic might just be real. With this new knowledge and the help of her new friends, will she be able to find her father? Will she be able to save her sister? Or is Zinnia already beyond being saved?